Antivibration support for instruments



Nov. 16, 1937. c. L.' sEwARD, JR 2,099,375

` ANTIVIBRATION SUPPORT oa INSTRUMENTS Filed May 7, 1935 s sheets-sheet 1 INVENTOR. C/a/ence Lee- .Sewarcez c. L. sEwARD, JR

ANTIVIBRATION SUPPORT FOR INSTRUMENTS Nov. 16, '1937.

Filed May '7, 1935 5 Sheets-Sheet- 2r INVENTOR. C/a/'ence ee Sen/0rd,@ BY l Nov. 16 1937. c. L- sEwARn, JR

ANTIVIBRATION SUPPORT FOR INSTRUMENTS .Filed May 7. 1935 3 Sheets-Sheet 3 Patented Nov. 16, 1937 U'Nlrao STAT-Es PATENT OFFICE y AN'nvr'BaA'noN SUPPORT Fon ms'rnumzn'rsA f ClareneeLee-Seward, 'Jl'.,VWashingtontuilL C., as-v.

signor' to Bendix Aviation Corporation, South Bend, Inds'fa corporation o! ,applicativa-May 'if i935, sei-a1 No; 20,5237

. (c1. ziaisn The present invention'relat indicating instruments such, for example, as are 'adapted-for Y l5 Broadly, however, oneof the principal objects' is the provision of a novel shock-absorbing or anti-vibration support for any instrument which may be subjected to vibrations whereby vibration of the instrument is substantially prevented both horizontally and vertically..

In accordance with the invention there is provided'an anti-vibration or shock-absorbing support constituted by three substantially horizontal supporting members disposed one above the other in parallel planes, one of said'member's beingv provided with means for securing an instrument thereto and another one being provided with the third member for connecting said members together and for absorbing horizontal vibrations. 'Ihe two yielding means and the center supporting L member thus also constitute an interconnecting yielding structure between the two outer supporty ing members whereby an instrument carried by one of said outer members may be resiliently connected to an instrument panel by means of the L other outer member. Preferably, vertical guiding means are also provided between said one of the rst two members and the third member to facilitate relative vertical movement therebetween.

The vertical guiding means may also be made to ,0 provide a relative rocking movement between the member secured to the panel and the member carrying the instrument, if desired.

A specific object of the invention is to provide a novel shock-absorbing structure for mounting i5 an indicating instrument on an instrument panel and embodying-a' frame constituted by three substantially horizontal and parallel plates disposed one'above the other, one of which is provided with means IorsecurmgY an instrument thereto and another of` which is provided with means vfor se- 5 curing it to; the instrument panel so as to project therefrom substantially at iight angles thereto. the third plate .being interposed between said first two plates and having two sets of openings therein, yielding means interposed betweenl one of the rst two plates and the third plate vfor preventing transmission of verticalvibrations from the instrument panel to the instrument and 'comprising a plurality of pins carried by said one of the rsttwo plates and projecting toward a. respective opening of one of the'sets in said third plate, a cup-shaped member in each of the open- --ings toward which said pins project and adapted to receive said pins upon relative vertical movement between they third plate and said one of the ilrst two plates, said cupshaped members having flanges at their open ends to provide an abutment therefor against said third plate, a compression coil spring encircling each pin and pro.- jecting into the associated cup-shaped member 25 whereby yielding relative movement may take place in a vertical direction between said third 4 plate and said one of the iirst two' plates, and a second yielding means interposed between said third plate and the other of the first two plates for preventing' transmission of horizontal vibrations from the instrument panel to the instrument, said last-named yielding means comprising a plurality of pins carried by the other of the nr'st two plates and projecting through a. respec- 35 -tive opening of the other set in said thirdplate,

springs interposed between said pins in said other openings and said third plate, and a bearing washer disposed about each of said other openings on that side. of said third plate on which the 40 weight of the instrument is exerted and providing bearing surfaces between said third plate and the other of said rst two plates to permit and facilitate relative sliding movement in a horizontal planebetween said third plate and the 4other of 45 said ilrst two plates in opposition to the lateral compression force of said springs.

'I'he above and other objectsand advantages of the invention will appear more fully hereinafter from a consideration of the detailed description which follows, taken together with the accompanying drawings wherein one embodiment of the invention is illustrated. It is to be expressly understood, however, that the drawings are for the purpose of illustrationand'description only 55 specification, as shown in the drawings by way of. example, and as nally pointed out in the claims.

In the drawings wherein like reference characters refer to like parts throughout the several views,

Fig. 1 is a front view, in elevation, of one form of novel shock-absorbing support embodying the invention and having a magnetic compass mounted thereon by way of example;

Fig. 2 is a side elevation of the structure shown in Fig. 1 as viewed from the left and mounted on an instrument panel;

Fig. 3 is a top plan view of Fig, 2 with th compass and panel removed;

Fig.4 is a section taken on l-ine 4-4 of Fig. 3 with the compass and panel shown in dotted lines;

Fig. 5 is a substantially full-size rear view, partly in section, of. the support with the compass removed; f

Fig. 6 is a section taken on line 6--6 of Fig. 5;

Fig. 7 is a similar section taken on line 1-1 of Fig. 5;

Fig. 8 is an enlarged detail section taken online 8- 8 of Fig. 4, showing oneof the vertical shocky absorbing elements;

line 9-9 of Fig. 5, showing one of the horizontal shock-absorbing elements;

Fig. 10 is a full-size rear view of another form of anti-vibration support embodying the invention whereby relative rocking movement/may take place between the instrument and its support; l

Fig. 11 is a section taken on line II-II of Fig. 10; and

Fig. 12 is a similar section taken on line I2--I2 of Fig. 10.

Referring now `to the drawings, and more particularly to Figs. 1 to 9, inclusive, the` novel shock-absorbing oranti-vibration support of the horizontal and parallel plates l0, II and I2 disosed one'above the other and, in the present nstance, the plate III constitutes the bottom plate and the plate I2 constitutes thevuppermost plate, with plate II interposed between said plates I and I2. The bottom plate I0 is provided with means for securing it to a xed support such, for example, as an instrument panel I3 (Fig. 2) of an aircraft, and, as illustrated, said means are constituted by upwardly extending triangular walls I4 and I5 disposed on opposite sides of the plate I0 and formed integrally therewith, said walls having portions I6 and I1 bent inwardly at right angles and towards each other (Figs. 1 and 3). Bent in portion I6 is provided with tapped holes I 8 and I9 and the bent in portion I'IA is provided with a similar pair of `tapped holes l2li and 2l for receiving screws, two of ,which are shown at 22 and 23 (Fig. 2),

i and by means of which said plate I0 is secured to the instrument panc i3 so as to project therefrom at substantially right angles thereto.

The uppermost plate I2 is provided with means for securing an instrument thereto such, for

Fig. 9 is an enlarged detail section taken on invention comprises, in the form shown, threeA example, as a magnetic compass 24, said means being similar' to those of the lower plate IDand constituted by upwardly extending triangular walls 25 and `26 having right-angularly bent-in portions 21 and 28, each having a pair of countersunk holes for receiving screws' 29, 30, 3l and 32 (Fig. 1) by means of which the instrument 24 is secured to said plate I2.

The plates I0, II and I2 are resiliently interconnected in a manner and for a purpose which will appear hereinafter.

Means are now provided for preventing the transmission of vertical vibrations to the instrument 24 from the panel I3 when the plate I0 is secured thereto, said means comprising three vertical shock absorbers triangularly spaced between the plate I0 and plate II. Two -of said vertical shock absorbers are shown at 33 and 34 in Fig. 1, and the third is shown at 35 in Fig. 4. The first two, namely, 33 and 3 4, are located substantially in the front corners of the center plate II while thev third one, namely, 35 is located substantially centrally of the rear edge of said center plate II, the triangular arrangement of saidshock absorbers 33, 34 and 35 being readily perceived from the top plan view shown in Fig. 3.

All three of said shock-absorbing members 33, 34 and 35 are identical in structure and an enlarged detailed section of one of them is shown in Fig. 8. From the latter iigure it will be seen that each of said vertical shock absorbers comprises a pin 36 carried by the`lower plate III and projecting upwardly toward an opening 31 provided in the center plate II. A cup-shaped member 33 is provided in the opening 31 with its open end disposed toward the pin 36 so as to receive the pin 36 upon relative vertical movement between the plates I0 and II. A coil spring 39 is provided about the pin 36 and has one end thereof projecting into and abutting against the closed end of thecup-shaped member 38, and its other member in order that it may receive in telescopic engagement therewith a guide pin 42a secured to the closed or upper end of the cupshaped member 38 whereby the cup-shaped member and, hence, the plates I0 and II are guided in a vertical direction upon vertical relative movement between said plates. The pin 36, however, may be a solid pin 36a (Fig. 10) and the guide pin 42a. may then be eliminated so that there may be obtained a slight relative rocking movement between the plates I0 and II about said pin 36a, if desired, as will appear later in connection with the embodiment shown in Fig. 10, the main object ofthe invention being the provision of a plurality of such pinsas 36, either tubular or solid, on the plate I0 and projecting toward a respective opening 31 in the center plate II, a cup-shaped member such as 38 in each of saidV openings and adapted to receive the 'pin 36 upon relative vertical movement between the plates I0 and I I and a compression coil spring encircling the pin 36 and projecting into the cupshaped member 39 whereby yielding relative movement may take place in a vertical direction between the plates I and II. triangular spaced relation of the shock-absorbing members 33, 34 and 35 the plates III and II are maintained substantially parallel at all times, the 'plate II being supported on the plate III by means 2, 5, 6 and 7, said means comprise a pair of op-y positely disposed vertical upwardly tapering arms 43 and 44 carried by the plate I0 and projecting upwardly therefrom at the side edges thereof in substantially the same plane with the side walls I4 and I5, the latter being cut away, as shown in Fig. 2, to accommodate said arms. The arms may be separate members or formed out of a single member 42 (Fig. 5) bent upwardly at its end to provide said arms 43 and 44. In the present instance, the arms 43 and 44 are secured to the plate I6 by riveting the member 42 to said plate III', as shown in section in Fig. 4.

Another pair of oppositely disposed vertical upwardly tapering arms 45 and 46 are provided which are carried bythe center plate II and which project upwardly therefrom at the side edges thereof, as shown in Fig. 5. 'I'he arm 45 is disposed adjacent the arm 43 while the arm 46 is `Adapted to slide within the slot or groove 41 are a pair of pins 49 and 56 carried by the arm 43 -and projecting therefrom at right angles thereto into the slot 41, as shown in Fig. 5, the pin 49 being at the upper lend of said arm 43 andthe pin 50 being at the lower end thereof. Securedto or formed integrally with the pins 49 and 59 are a. pair of discs and 52, respectively, through which said pins 49 and 50 project and the surfaces of which are polished in order to provide smooth bearing surfaces which cooperate with thev face of the -arm 45. A corresponding pair oi' pins 53and 54 are provided on the upper and lower end oi' the arm 44 for sliding movement in slot orgroove 48 ofthe arm 46 (Figs. 6 and 7,), said pins 53 and 54 beinglikewise provided with corresponding discs 55 and 56 Afor cooperation with the. face. of the arm 46; l

Thus, it will be seen that the pins 49, 56. and 53, 54 are adapted to slide within their respective grooves 41 and 48 and thereby guide the plates I6 and II upon vertical relative movement therebetween. l In orderv to prevent the pins. 49 and ,53 from sliding completely out of .their,respectiveY grooves and `'46 stops are proand 56 which are rigidly secured to said arms By virtue of the transmission of horizontal vibrations to the instrument 24 from the panel I3 when the plate shock-absorbing elements are shown at 6I and 62 in Fig. 5 andthe third is shown at 63 in Fig. 1. The first two, namely, 6I and 62 are located substantially in the rear corners of the center plate II, while the third one, namely, 63 is located substantially centrally of the front edge of said center plate, the triangular arrangement of said-elements being readily perceived from the top plan view shown in Fig. 3.

In order to prevent said shock-absorbing members 6I, 62 and 63 from striking the lower plate I Il upon relative vertical movement between said plate I0 and the plate Il, the former is provided with a circular opening under each of said shock-absorbing elements, one of said openings being shown at 64 in Fig. 4, which cooperates with the shock-absorbing member 63. The other two openings for the members 6I and 62 are shown at 65 and 66, respectively, in Fig. 5.

Allthree of said horizontally acting shock-absorbing members 6I, 62 and 63 are identical in structure and an enlarged detail section of one of them is shown in Fig. 9. From this figure, it will be seen that each of the horizontally acting shock-absorbers comprises a pin 61 carried by and secured to the plate I2 in any suitable manner as by means of a nut 68 disposed on one side of the plate I2 and another nut 69 disposed on'the other side ofv said-plate. 'Ihe pin 61 is arranged to project into and extend through a housing or collar 1I) rigidly secured, as by means of a press t, in an opening in the center plate II, said housing or collar `1li being of some suitable metal such, for example, as phosphor-bronze or stellite and being provided-with an annular flange 1I at 'the upper end thereof so as to present a bearing surface which is adaptedv to cooperate with a similar bearing surface provided by a washer 12 which is also of phosphor-bronze or stellite.A The washer is disposed about the pin 61 and. held in* engagement with the bearing surface of the collar 1I by means .of a lock washer 13. Another-washer 14 which is like washer12 is provided at the lower end pf the housing 10 and forms a bearing surface which cooperates with the lower periphery of said housing 10 and is held in engagement therewith by a lock washer 15, a lock nut 16 and a retaining nut 11. Thus, it will be seen that upon relative movement between plates II and I2 in any direction parallel to said plates a sliding movement will take place between washers 12, 14 and the cooperating surfaces provided at the ends of the housing 16. Within the housing 1I) is a flat coil spring 18 having one end connected to the pin 61 and its other end to the inner wall of the housing 10` so that upon relative sliding movement between the plates II and I2, the spring 18 functions tooppose suchmovement and thereby provides a resilient connection between said plates by means of which any horizontal vibrations of the plate Aas In operation, if the supporting plate I0 is secured to an instrument panel on an airplane by means of the portions I6 and II of the side walls |4'and I5 of said plate I0, the latter will be subject to vibrations which are generally produced by the internal combustion engine or engines 'operating the plane and by forces acting' on the plane in maintaining it in flight, said vibrations acting in all directions but may be resolved into horizontal and vertical components. If an instrument be secured to the plate I2 by means of the portions 21 and 28 of the side walls 25 and- 26, the vertical component of vibrations will be preventedl from being transmitted to said instrument by virtue of the fact that vertical relative movement will take place between the plates I0 and II against the springs 39 of the vertical shock-absorbing elements 33, 34 and 35, respectively, there being no relative vertical movement between the plates II and I2. The horizontal component of vibrations will be prevented from being transmitted from the plate I0 to the plate I2 by vii-tue of the fact that relative horizontal movement takes place between the plates Il and I2 against the force of the at coil spring 'I8 of the horizontal shock-aborbing members 6I, 62 and 63, there being no relative horizontal movement between the plates I9 and I I. As previously pointed out, the vertical relative movement between plates Ill and I I and, hence, between plates I6 and I2 is guided by means of the guide arms 43, 45 and 44, 46 and also by means of the guide pins 42a of the respective vertical shock-absorbing members 33, 34 and 35. Thus, all vibrations acting on the plate I0 are prevented from being transmitted to the instrument carried by the plate I2.

Referring now t'o Figs. 10, 11 and 12, there is illustrated another embodiment of the invention wherein the guide pins 42a are eliminated in the vertical-shock-absorbing members 33, 34 and 35 and.- the guide arms 43, 45 and 44, 46 are so constructed and arranged that pivotal rocking movement may take place between the plates I0 and I I in a direction perpendicular to the plane of the paper as viewed in Fig. 10, and about Aa horizontal axis passing through the upper ends of the guide arms 43 and 44. In this embodiment of the invention and for the purpose stated the guide arm 43 is provided at its upper end with a flat disc-like member 19 which is journaled for rotary movement in said guide arm 43 by means of a-projection secured to or formed integrally with the disc member 19. The arm 44 on the opposite side of the plate I0 is provided with a corresponding disc-like member 8 I which is journaled in said arm 44 by means of a projection 82 (Fig. l1). The disc-like members 19 and 8| are provided with vertical slots 83 (Fig. 10). and 84 (Fig. 11), respectively. Arranged to cooperate with the slots 83 and 84 there are provided tongues 85 and 86 formed integrally with disc-like members 81 and 88 carried by the upper ends of the guide arms 45 and 46. Upon relative vertical movement between the plates I0 and Il the tongues 85 and 86 slide longitudinally within their respective slots' 83 and 84 and the cooperating surfaces of the disc-like members 19, 81 and 8|, 88 provide bearing surfaces to facilitate such sliding movement and,

therefore, said sur-faces are given a high polish. Since, however, the disc-like members 19 and 8| are arranged for rotary movement within their respective guide arms 43 and 44, a pivotal movement may take place between the plates I9 and I I in a direction perpendicular to the plane of the paper, as viewed in Fig. 10, and about an axis passing through the centers of the disc-like members 'I9 and 8 I. Such pivotal movement may take place independently'of or simultaneously with the vertical relative movement. In order to facilitate the pivotal movement, a friction disc 89 is provided at the lower end of the arm 43 and a corresponding friction disc 90 is provided at the lower end of thearm 44, said discs being more or less loosely mounted in said arms by means of suitable pins formed integrally with said discs. The friction discs 89 and 90 are arranged to cooperate with friction surfaces 9| and 92 provided at the lower ends of the guide arms 45 and 46, respectively, and in order to maintain said friction discs 89 and 90 in engagement with their cooperating friction surfaces 9| and 92, means are provided in the form of leaf springs 93 and 94 secured to the outer walls of the guide arms 43 and 44, respectively. The springs 93 and 94 bear against the ends of the pins of the friction discs 89 and 90, respectively, as shown in Figs. 10 and 11. i

In order to limit the vertical relative movement between the plates I9 and II the guide arms 43 and 44 are provided with transversely extending projections 95 yand 96, respectively, which cooperate with stop screws I9`| and 98 carried by the guide arms 45 and 45.

A slight rocking movement may also take place in a direction in the plane of the paper by virtue of the fact that guide tongues 85 and 86 work loosely in their cooperating slots 83 and 84 and if the right-hand end of the plate II, as viewed in Fig. l0, be lowered ,or the corresponding end of the plate I0 be raised, the top part of tongue 86 will recede from the slot 84 and its lower part will move farther into slot 84 while the upper part of tongue 85 will move farther into the slot 83 and its lower part will recede from slot 83. At this time the leaf spring 93 on the arm 43 will urge the friction disc 89 toward the friction surface 9| which has been slightly moved away from said disc in a direction toward the left as viewed in Fig. l0 due to the rocking movement.

The above-mentioned pivotal and rocking movements between the plates I0 and I I are permitted because the guide pins 42a of the vertical shock-absorbing members 43, 44 and 45 have been eliminated and, therefore, the vertical coil springs 39 of said members act to oppose these movements and, hence, provide a resilient shock-absorbing action not only in the vertical direction but in two mutually perpendicular horizontal directions when the pivotal and rocking movements take place. Consequently, with the embodiment of the invention shown in Figs. 10, l1 and 12 transmission of vibrations to an instrument carried by the plate I2 are prevented to a somewhat greater extent than in the embodiment shown in Figs. 1

instrument whereby vibrations in both the horizontal plane and the vertical plane are substantially prevented from being transmitted from the support to the instrument and particularly when the support is mounted on an instrument panel of an aircraft. If a compass be mounted on the support the magnetic card of the compass will be prevented from spinning on its pivot 4thereby providing accurate indications of compass direction and facilitating reading of the card because the graduations on the card do not become blurred as they otherwise do when the Vibrations are not eliminated.

Although only two embodiments of the invention. For example, the supports shown in Figs.

and 10 might be mounted on the instrument panel in an inverted position so that the instrument may be suspended from said support instead of lbeing carried thereon, the broad feature of the invention being the relative arrangement,

connection and cooperation of the plates i0, Il

and I2. Reference is, therefore, to be had to the appended claims for a definition of the limits of the invention.

What is claimed is:

1. An anti-vibration support for mounting an indicating instrument on a xed support, comprising a frame constituted by three substantially horizontal and parallel plates disposed one above the other, one of which is provided with means for securing an instrument thereto and another of which is provided with means for securing it to the iixed support, the third plate being interposed between said first two plates and having two sets of openings therein, yielding means interposed between one of the first two plates and theA third plate for preventing transmission of vertical vibrations from the` fixed support tothe instrument and comprising a plurality of pins carried by said one of the first two plates and projecting toward a respective opening of one of the sets in said third plate, a cupshaped member in each of the openings toward which said pins project and adapted to receive said pins upon relative movement between the third plate and said one of the first two plates, said cup-shaped members having flanges 'at their open ends to provide an abutment therefor against said third plate, a vertically extending compression coil spring encircling each pin and projecting into `:the associated cup-shapedmember whereby yielding relative movement may take place in a vertical direction between said third plate and said-one of the rst two plates, and second yielding means interposed between said third plate and the other of the first two plates for preventing transmission of horizontal vibrations i'rom the fixed support to the instrument,

said last-named yielding means comprising a.

of the instrument is exerted and providing bear-y ing "surfaces between said third plate and the other of said first two plates to permit and facilitate relative sliding movement in a horizontal plane between said third plate and the other ofsaid first two plates in opposition to the lateral compression rforce of said flat coil springs.

2. An anti-vibration support for mounting an l indicating instrument on a fixed support, comprising a frame constituted by-three substan- .tially horizontal and parallel plates disposed one above the other, one of which is provided with means for securing aninstrument thereto and another of which is provided with means for securing il? to the fixed support, the third plate being interposed 'between ,said first two plates and having two sets of openings therein, yielding means interposed between one of the rst two plates and the third plate for preventing transmission of vertical vibrations from the fixed support to the instrument and comprising a plurality of pins carried by said one of the first two plates and projecting toward a respective opening of oneof the sets in said third plate, a cup-shaped member in each of the openings toward which said pins project and adapted tol third -plate and said one of the first two plates,

second yielding means interposed between said third plate and the other of the first two plates for preventing transmission of horizontal vibrations from the fixed support to the instrument, said last-named yielding means comprising a pluralityof pins carried by the other of the first two plates and projecting through a respective opening of the other set in said third plate, a 'fiatcoil spring interposed between each of said pins in said other openings and said third plate, and a bearing washer disposed about each of said pins and their respective openings and on that side of said third plate on which the weight of the instrument is exerted and providing bearing surfaces between said third plate and the other of said first two plates to permit and facilitate relative sliding movement in a horizontalplane between said' third plate and the other of said rst two plates in opposition to the lateral compression force of said flat coil springs, and guiding means between said one of the first two plates and the third plate to facilitate, relative vertical movement therebetween.

3. Amanti-vibration support for mounting an indicating instrument on a fixed support, comprising la frame constituted by three substantially horizontal and parallel plates disposed one above the other, one of which is provided with means for securing an instrument thereto and anotherpf which is provided with means for securing it to the fixed support, the third plate being interposed between said first two plates and having two sets of openings therein, yielding means interposed between one of the first two plates and the third plate for preventing transmission of vertical vibrations from the xcd support to the vinstrument and comprising a plurality of pins carried by said one of the rst two plates and projecting toward a respective opening of one of the sets in said third plate, a cup-shaped member in each of the openings toward which said pins project and adapted to receive said pins upon relative movement between the third plate and said one of the first two plates, said cupshaped members having anges at their 'fopen ends to provide an abutment therefor against said third plate, a vertically extending compression coil spring encircling each pin and projecting into 4the associated cup-shaped member whereby yielding relative movement may take place in a vertical direction between-said third plate and*4 said one of the rst two plates, second yielding means interposed between said third plate and the other of the iirst two plates for preventing transmission of horizontal vibrations from the fixed support to the instrument, said last-named yielding means comprising a plurality of pins carried by the other of the rst two plates and projecting through a respective opening of the other set in saidthird plate, a lat coil spring interposed between each of said pins in said other openings and said third plate, and a bearing washer disposed about each of said pins and their respective openings and on that side of said third plate on which the weight of the instrument is exerted and providing bearing surfaces between said third plate and the other of said rst two plates to permit and facilitate relative sliding movement in a horizontal plane between said,

third plate and the other of said rst two plates in opposition to the lateral compression force of said flat coil springs, and guiding means between said one of the first two plates and the third plate to facilitate relative vertical movement therebetween, said guiding means including means providing rocking movement between said one of the first two plates and the third plate in a horizontal direction.

4. An anti-vibration support comprising three substantially horizontal supporting members disposed one above the other in parallel pla-nes, one of said members being provided with means for securing thereto a device which is to be prevented from vibrating and another one of said members being provided with means for securing it to a `fixed support susceptible to vibration, the third member bei -g interposed between said first two members, vertically yielding means between one of said rst two members and the third member for' absorbing vibrations in a vertical direction, and horizontally yielding means between the other of said rst two members and the third member for absorbing vibrations in a horizontal direction and slidable means cooperating with said horizontally yielding means for facilitating relative horizontal movement.

5. An anti-vibration support comprising three substantially horizontal supporting members disposed one above the other in parallel planes, one of said members being p'rovided with means for securing thereto a device which is to be prevented from vibrating and another-one of Said members being provided with means for securing it to a xed support susceptible to vibration, the third member being interposed between said first two members, vertically yielding means between one of said first two members and the third member for absorbing vibrations in a vertical direction, horizontally yielding means between the other of said first two members and the third member for absorbing vibrations in a horizontal direction, and guiding means between said one of the rst two members and said third member for facilitating vertical relative movement therebetween.

6. An anti-vibration support comprising three substantially horizontal supporting members disposed one above the other in parallel planes, one of said members being provided with means for securing thereto a device which is to be prevented from vibrating and another one of said members being provided with means for seeming it to a xed support susceptible to vibration, the third member being interposed between said rst two members, vertically yielding means between one of said iirst two members and the third member for absorbing vibrations in a vertical direction,

horizontally yielding means between the other of said rst two members and the third member for absorbing vibrations in a horizontal direction, and guiding means between said one of the first two members and said third member for facilitating vertical relative movement therebetween, said guiding means including means providing' rocking movement between said one of the first two members and the third member about a horizontal axis.

CLARENCE SEWARD, JR. 

